[Chromium API] Disambiguate allowJavaScript from didNotAllowScript

https://bugs.webkit.org/show_bug.cgi?id=35205 Patch by Adam Barth <abarth@webkit.org> on 2010-02-24 Reviewed by Darin Fisher. WebCore: For clients that want to show a user interface element when JavaScript was blocked on a page, we need to disambiguate between querying the client for whether JavaScript is enabled from actually failing to execute some script. This patch adds a new FrameLoaderClient callback for when WebCore would like to execute JavaScript but fails to because JavaScript is disabled. This patch also touches every client of canExecuteScripts so they can indicate whether we should make this callback. I was hoping there was a better choke point, but my first two attempts were wrong in subtle ways. pkasting points out that this will be easy to screw up in the future, so it's better to make all the clients be explicit. * WebCore.PluginHostProcess.exp: * bindings/ScriptControllerBase.cpp: (WebCore::ScriptController::canExecuteScripts): (WebCore::ScriptController::executeScript): * bindings/js/JSEventListener.cpp: (WebCore::JSEventListener::handleEvent): * bindings/js/JSLazyEventListener.cpp: (WebCore::JSLazyEventListener::initializeJSFunction): * bindings/js/ScheduledAction.cpp: (WebCore::ScheduledAction::execute): * bindings/js/ScriptController.cpp: (WebCore::ScriptController::bindingRootObject): (WebCore::ScriptController::windowScriptNPObject): (WebCore::ScriptController::jsObjectForPluginElement): (WebCore::ScriptController::executeScriptInWorld): * bindings/js/ScriptController.h: (WebCore::): * bindings/js/ScriptControllerMac.mm: (WebCore::ScriptController::windowScriptObject): * bindings/js/ScriptDebugServer.cpp: (WebCore::ScriptDebugServer::setJavaScriptPaused): * bindings/js/ScriptEventListener.cpp: (WebCore::createAttributeEventListener): * bindings/js/ScriptState.cpp: (WebCore::scriptStateFromNode): * bindings/v8/ScriptController.cpp: (WebCore::ScriptController::windowScriptNPObject): (WebCore::ScriptController::createScriptObjectForPluginElement): * bindings/v8/ScriptController.h: (WebCore::): * bindings/v8/ScriptEventListener.cpp: (WebCore::createAttributeEventListener): * bindings/v8/V8Proxy.cpp: (WebCore::V8Proxy::retrieve): * dom/ScriptElement.cpp: (WebCore::ScriptElementData::evaluateScript): * dom/XMLTokenizerLibxml2.cpp: (WebCore::XMLTokenizer::startElementNs): * html/HTMLMediaElement.cpp: (WebCore::HTMLMediaElement::controls): * html/HTMLTokenizer.cpp: (WebCore::HTMLTokenizer::parseTag): (WebCore::HTMLTokenizer::processToken): * inspector/InspectorController.cpp: (WebCore::canPassNodeToJavaScript): * loader/FrameLoader.cpp: (WebCore::FrameLoader::isProcessingUserGesture): (WebCore::FrameLoader::open): (WebCore::FrameLoader::dispatchDidClearWindowObjectsInAllWorlds): (WebCore::FrameLoader::dispatchDidClearWindowObjectInWorld): * loader/FrameLoaderClient.h: (WebCore::FrameLoaderClient::didNotAllowScript): WebKit/chromium: Plumb didNotAllowScript through Chromium's WebKit API. * public/WebFrameClient.h: (WebKit::WebFrameClient::didNotAllowScript): * src/DebuggerAgentImpl.cpp: (WebKit::DebuggerAgentImpl::createUtilityContext): * src/FrameLoaderClientImpl.cpp: (WebKit::FrameLoaderClientImpl::didNotAllowScript): * src/FrameLoaderClientImpl.h: * src/WebFrameImpl.cpp: (WebKit::WebFrameImpl::bindToWindowObject): WebKit/mac: Make these two callsites explicit about not running script immediately. * Plugins/Hosted/NetscapePluginInstanceProxy.mm: (WebKit::NetscapePluginInstanceProxy::getWindowNPObject): (WebKit::NetscapePluginInstanceProxy::demarshalValueFromArray): Canonical link: https://commits.webkit.org/46509@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@55207 268f45cc-cd09-0410-ab3c-d52691b4dbfc
WebKit · Feb 25, 2010 · f3ca3bd · f3ca3bd
1 parent e97f2af
commit f3ca3bd
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diff --git a/WebCore/ChangeLog b/WebCore/ChangeLog
@@ -1,3 +1,77 @@
+2010-02-24  Adam Barth  <abarth@webkit.org>
+
+        Reviewed by Darin Fisher.
+
+        [Chromium API] Disambiguate allowJavaScript from didNotAllowScript
+        https://bugs.webkit.org/show_bug.cgi?id=35205
+
+        For clients that want to show a user interface element when JavaScript
+        was blocked on a page, we need to disambiguate between querying the
+        client for whether JavaScript is enabled from actually failing to
+        execute some script.
+
+        This patch adds a new FrameLoaderClient callback for when WebCore would
+        like to execute JavaScript but fails to because JavaScript is disabled.
+
+        This patch also touches every client of canExecuteScripts so they can
+        indicate whether we should make this callback.  I was hoping there was
+        a better choke point, but my first two attempts were wrong in subtle
+        ways.  pkasting points out that this will be easy to screw up in the
+        future, so it's better to make all the clients be explicit.
+
+        * WebCore.PluginHostProcess.exp:
+        * bindings/ScriptControllerBase.cpp:
+        (WebCore::ScriptController::canExecuteScripts):
+        (WebCore::ScriptController::executeScript):
+        * bindings/js/JSEventListener.cpp:
+        (WebCore::JSEventListener::handleEvent):
+        * bindings/js/JSLazyEventListener.cpp:
+        (WebCore::JSLazyEventListener::initializeJSFunction):
+        * bindings/js/ScheduledAction.cpp:
+        (WebCore::ScheduledAction::execute):
+        * bindings/js/ScriptController.cpp:
+        (WebCore::ScriptController::bindingRootObject):
+        (WebCore::ScriptController::windowScriptNPObject):
+        (WebCore::ScriptController::jsObjectForPluginElement):
+        (WebCore::ScriptController::executeScriptInWorld):
+        * bindings/js/ScriptController.h:
+        (WebCore::):
+        * bindings/js/ScriptControllerMac.mm:
+        (WebCore::ScriptController::windowScriptObject):
+        * bindings/js/ScriptDebugServer.cpp:
+        (WebCore::ScriptDebugServer::setJavaScriptPaused):
+        * bindings/js/ScriptEventListener.cpp:
+        (WebCore::createAttributeEventListener):
+        * bindings/js/ScriptState.cpp:
+        (WebCore::scriptStateFromNode):
+        * bindings/v8/ScriptController.cpp:
+        (WebCore::ScriptController::windowScriptNPObject):
+        (WebCore::ScriptController::createScriptObjectForPluginElement):
+        * bindings/v8/ScriptController.h:
+        (WebCore::):
+        * bindings/v8/ScriptEventListener.cpp:
+        (WebCore::createAttributeEventListener):
+        * bindings/v8/V8Proxy.cpp:
+        (WebCore::V8Proxy::retrieve):
+        * dom/ScriptElement.cpp:
+        (WebCore::ScriptElementData::evaluateScript):
+        * dom/XMLTokenizerLibxml2.cpp:
+        (WebCore::XMLTokenizer::startElementNs):
+        * html/HTMLMediaElement.cpp:
+        (WebCore::HTMLMediaElement::controls):
+        * html/HTMLTokenizer.cpp:
+        (WebCore::HTMLTokenizer::parseTag):
+        (WebCore::HTMLTokenizer::processToken):
+        * inspector/InspectorController.cpp:
+        (WebCore::canPassNodeToJavaScript):
+        * loader/FrameLoader.cpp:
+        (WebCore::FrameLoader::isProcessingUserGesture):
+        (WebCore::FrameLoader::open):
+        (WebCore::FrameLoader::dispatchDidClearWindowObjectsInAllWorlds):
+        (WebCore::FrameLoader::dispatchDidClearWindowObjectInWorld):
+        * loader/FrameLoaderClient.h:
+        (WebCore::FrameLoaderClient::didNotAllowScript):
+
 2010-02-24  Adam Barth  <abarth@webkit.org>
 
         Reviewed by Darin Fisher.

diff --git a/WebCore/WebCore.PluginHostProcess.exp b/WebCore/WebCore.PluginHostProcess.exp
@@ -9,7 +9,7 @@ __ZN7WebCore13IdentifierRep3getEi
 __ZN7WebCore13IdentifierRep3getEPKc
 __ZN7WebCore13IdentifierRep7isValidEPS0_
 __ZN7WebCore16ScriptController16createRootObjectEPv
-__ZN7WebCore16ScriptController17canExecuteScriptsEv
+__ZN7WebCore16ScriptController17canExecuteScriptsENS_33ReasonForCallingCanExecuteScriptsE
 __ZN7WebCore16ScriptController24jsObjectForPluginElementEPNS_17HTMLPlugInElementE
 __ZN7WebCore6String26fromUTF8WithLatin1FallbackEPKcm
 __ZN7WebCore6String8fromUTF8EPKcm
diff --git a/WebCore/bindings/ScriptControllerBase.cpp b/WebCore/bindings/ScriptControllerBase.cpp
@@ -31,14 +31,17 @@
 
 namespace WebCore {
 
-bool ScriptController::canExecuteScripts()
+bool ScriptController::canExecuteScripts(ReasonForCallingCanExecuteScripts reason)
 {
     // FIXME: We should get this information from the document instead of the frame.
     if (m_frame->loader()->isSandboxed(SandboxScripts))
         return false;
 
     Settings* settings = m_frame->settings();
-    return m_frame->loader()->client()->allowJavaScript(settings && settings->isJavaScriptEnabled());
+    const bool allowed = m_frame->loader()->client()->allowJavaScript(settings && settings->isJavaScriptEnabled());
+    if (!allowed && reason == AboutToExecuteScript)
+        m_frame->loader()->client()->didNotAllowScript();
+    return allowed;
 }
 
 ScriptValue ScriptController::executeScript(const String& script, bool forceUserGesture)
@@ -48,7 +51,7 @@ ScriptValue ScriptController::executeScript(const String& script, bool forceUser
 
 ScriptValue ScriptController::executeScript(const ScriptSourceCode& sourceCode)
 {
-    if (!canExecuteScripts() || isPaused())
+    if (!canExecuteScripts(AboutToExecuteScript) || isPaused())
         return ScriptValue();
 
     bool wasInExecuteScript = m_inExecuteScript;

diff --git a/WebCore/bindings/js/JSEventListener.cpp b/WebCore/bindings/js/JSEventListener.cpp
@@ -83,7 +83,7 @@ void JSEventListener::handleEvent(ScriptExecutionContext* scriptExecutionContext
             return;
         // FIXME: Is this check needed for other contexts?
         ScriptController* script = frame->script();
-        if (!script->canExecuteScripts() || script->isPaused())
+        if (!script->canExecuteScripts(AboutToExecuteScript) || script->isPaused())
             return;
     }
 

diff --git a/WebCore/bindings/js/JSLazyEventListener.cpp b/WebCore/bindings/js/JSLazyEventListener.cpp
@@ -79,7 +79,7 @@ JSObject* JSLazyEventListener::initializeJSFunction(ScriptExecutionContext* exec
         return 0;
 
     ScriptController* scriptController = frame->script();
-    if (!scriptController->canExecuteScripts())
+    if (!scriptController->canExecuteScripts(AboutToExecuteScript))
         return 0;
 
     JSDOMGlobalObject* globalObject = toJSDOMGlobalObject(executionContext, isolatedWorld());
@@ -93,7 +93,7 @@ JSObject* JSLazyEventListener::initializeJSFunction(ScriptExecutionContext* exec
             return 0;
         // FIXME: Is this check needed for non-Document contexts?
         ScriptController* script = frame->script();
-        if (!script->canExecuteScripts() || script->isPaused())
+        if (!script->canExecuteScripts(AboutToExecuteScript) || script->isPaused())
             return 0;
     }
 

diff --git a/WebCore/bindings/js/ScheduledAction.cpp b/WebCore/bindings/js/ScheduledAction.cpp
@@ -117,7 +117,7 @@ void ScheduledAction::execute(Document* document)
         return;
 
     RefPtr<Frame> frame = window->impl()->frame();
-    if (!frame || !frame->script()->canExecuteScripts())
+    if (!frame || !frame->script()->canExecuteScripts(AboutToExecuteScript))
         return;
 
     frame->script()->setProcessingTimerCallback(true);

diff --git a/WebCore/bindings/js/ScriptController.cpp b/WebCore/bindings/js/ScriptController.cpp
@@ -317,7 +317,7 @@ void ScriptController::updateSecurityOrigin()
 
 Bindings::RootObject* ScriptController::bindingRootObject()
 {
-    if (!canExecuteScripts())
+    if (!canExecuteScripts(NotAboutToExecuteScript))
         return 0;
 
     if (!m_bindingRootObject) {
@@ -344,7 +344,7 @@ PassRefPtr<Bindings::RootObject> ScriptController::createRootObject(void* native
 NPObject* ScriptController::windowScriptNPObject()
 {
     if (!m_windowScriptNPObject) {
-        if (canExecuteScripts()) {
+        if (canExecuteScripts(NotAboutToExecuteScript)) {
             // JavaScript is enabled, so there is a JavaScript window object.
             // Return an NPObject bound to the window object.
             JSC::JSLock lock(SilenceAssertionsOnly);
@@ -377,7 +377,7 @@ NPObject* ScriptController::createScriptObjectForPluginElement(HTMLPlugInElement
 JSObject* ScriptController::jsObjectForPluginElement(HTMLPlugInElement* plugin)
 {
     // Can't create JSObjects when JavaScript is disabled
-    if (!canExecuteScripts())
+    if (!canExecuteScripts(NotAboutToExecuteScript))
         return 0;
 
     // Create a JSObject bound to this element
@@ -444,7 +444,7 @@ ScriptValue ScriptController::executeScriptInWorld(DOMWrapperWorld* world, const
 {
     ScriptSourceCode sourceCode(script, forceUserGesture ? KURL() : m_frame->loader()->url());
 
-    if (!canExecuteScripts() || isPaused())
+    if (!canExecuteScripts(AboutToExecuteScript) || isPaused())
         return ScriptValue();
 
     bool wasInExecuteScript = m_inExecuteScript;

diff --git a/WebCore/bindings/js/ScriptController.h b/WebCore/bindings/js/ScriptController.h
@@ -62,6 +62,11 @@ class XSSAuditor;
 
 typedef HashMap<void*, RefPtr<JSC::Bindings::RootObject> > RootObjectMap;
 
+enum ReasonForCallingCanExecuteScripts {
+    AboutToExecuteScript,
+    NotAboutToExecuteScript
+};
+
 class ScriptController {
     friend class ScriptCachedFrameData;
     typedef WTF::HashMap< RefPtr<DOMWrapperWorld>, JSC::ProtectedPtr<JSDOMWindowShell> > ShellMap;
@@ -110,7 +115,7 @@ class ScriptController {
     bool processingUserGesture(DOMWrapperWorld*) const;
     bool anyPageIsProcessingUserGesture() const;
 
-    bool canExecuteScripts();
+    bool canExecuteScripts(ReasonForCallingCanExecuteScripts);
 
     // Debugger can be 0 to detach any existing Debugger.
     void attachDebugger(JSC::Debugger*); // Attaches/detaches in all worlds/window shells.

diff --git a/WebCore/bindings/js/ScriptControllerMac.mm b/WebCore/bindings/js/ScriptControllerMac.mm
@@ -107,7 +107,7 @@ - (NPObject *)createPluginScriptableObject;
 
 WebScriptObject* ScriptController::windowScriptObject()
 {
-    if (!canExecuteScripts())
+    if (!canExecuteScripts(NotAboutToExecuteScript))
         return 0;
 
     if (!m_windowScriptObject) {

diff --git a/WebCore/bindings/js/ScriptDebugServer.cpp b/WebCore/bindings/js/ScriptDebugServer.cpp
@@ -378,7 +378,7 @@ void ScriptDebugServer::setJavaScriptPaused(Frame* frame, bool paused)
 {
     ASSERT_ARG(frame, frame);
 
-    if (!frame->script()->canExecuteScripts())
+    if (!frame->script()->canExecuteScripts(NotAboutToExecuteScript))
         return;
 
     frame->script()->setPaused(paused);

diff --git a/WebCore/bindings/js/ScriptEventListener.cpp b/WebCore/bindings/js/ScriptEventListener.cpp
@@ -64,7 +64,7 @@ PassRefPtr<JSLazyEventListener> createAttributeEventListener(Node* node, Attribu
     // FIXME: We should be able to provide accurate source information for frameless documents, too (e.g. for importing nodes from XMLHttpRequest.responseXML).
     if (Frame* frame = node->document()->frame()) {
         ScriptController* scriptController = frame->script();
-        if (!scriptController->canExecuteScripts())
+        if (!scriptController->canExecuteScripts(AboutToExecuteScript))
             return 0;
 
         if (!scriptController->xssAuditor()->canCreateInlineEventListener(attr->localName().string(), attr->value())) {
@@ -96,7 +96,7 @@ PassRefPtr<JSLazyEventListener> createAttributeEventListener(Frame* frame, Attri
     String sourceURL;
 
     ScriptController* scriptController = frame->script();
-    if (!scriptController->canExecuteScripts())
+    if (!scriptController->canExecuteScripts(AboutToExecuteScript))
         return 0;
 
     if (!scriptController->xssAuditor()->canCreateInlineEventListener(attr->localName().string(), attr->value())) {

diff --git a/WebCore/bindings/js/ScriptState.cpp b/WebCore/bindings/js/ScriptState.cpp
@@ -54,7 +54,7 @@ ScriptState* scriptStateFromNode(DOMWrapperWorld* world, Node* node)
     Frame* frame = document->frame();
     if (!frame)
         return 0;
-    if (!frame->script()->canExecuteScripts())
+    if (!frame->script()->canExecuteScripts(NotAboutToExecuteScript))
         return 0;
     return frame->script()->globalObject(world)->globalExec();
 }

diff --git a/WebCore/bindings/v8/ScriptController.cpp b/WebCore/bindings/v8/ScriptController.cpp
@@ -389,7 +389,7 @@ NPObject* ScriptController::windowScriptNPObject()
     if (m_windowScriptNPObject)
         return m_windowScriptNPObject;
 
-    if (canExecuteScripts()) {
+    if (canExecuteScripts(NotAboutToExecuteScript)) {
         // JavaScript is enabled, so there is a JavaScript window object.
         // Return an NPObject bound to the window object.
         m_windowScriptNPObject = createScriptObject(m_frame);
@@ -406,7 +406,7 @@ NPObject* ScriptController::windowScriptNPObject()
 NPObject* ScriptController::createScriptObjectForPluginElement(HTMLPlugInElement* plugin)
 {
     // Can't create NPObjects when JavaScript is disabled.
-    if (!canExecuteScripts())
+    if (!canExecuteScripts(NotAboutToExecuteScript))
         return createNoScriptObject();
 
     v8::HandleScope handleScope;

diff --git a/WebCore/bindings/v8/ScriptController.h b/WebCore/bindings/v8/ScriptController.h
@@ -55,6 +55,11 @@ class String;
 class Widget;
 class XSSAuditor;
 
+enum ReasonForCallingCanExecuteScripts {
+    AboutToExecuteScript,
+    NotAboutToExecuteScript
+};
+
 class ScriptController {
 public:
     ScriptController(Frame*);
@@ -113,7 +118,7 @@ class ScriptController {
     // Check if the javascript engine has been initialized.
     bool haveInterpreter() const;
 
-    bool canExecuteScripts();
+    bool canExecuteScripts(ReasonForCallingCanExecuteScripts);
 
     // FIXME: void* is a compile hack.
     void attachDebugger(void*);

diff --git a/WebCore/bindings/v8/ScriptEventListener.cpp b/WebCore/bindings/v8/ScriptEventListener.cpp
@@ -56,7 +56,7 @@ PassRefPtr<V8LazyEventListener> createAttributeEventListener(Node* node, Attribu
 
     if (Frame* frame = node->document()->frame()) {
         ScriptController* scriptController = frame->script();
-        if (!scriptController->canExecuteScripts())
+        if (!scriptController->canExecuteScripts(AboutToExecuteScript))
             return 0;
 
         if (!scriptController->xssAuditor()->canCreateInlineEventListener(attr->localName().string(), attr->value())) {
@@ -89,7 +89,7 @@ PassRefPtr<V8LazyEventListener> createAttributeEventListener(Frame* frame, Attri
     String sourceURL;
 
     ScriptController* scriptController = frame->script();
-    if (!scriptController->canExecuteScripts())
+    if (!scriptController->canExecuteScripts(AboutToExecuteScript))
         return 0;
 
     if (!scriptController->xssAuditor()->canCreateInlineEventListener(attr->localName().string(), attr->value())) {

diff --git a/WebCore/bindings/v8/V8Proxy.cpp b/WebCore/bindings/v8/V8Proxy.cpp
@@ -560,7 +560,7 @@ V8Proxy* V8Proxy::retrieve(Frame* frame)
 {
     if (!frame)
         return 0;
-    return frame->script()->canExecuteScripts() ? frame->script()->proxy() : 0;
+    return frame->script()->canExecuteScripts(NotAboutToExecuteScript) ? frame->script()->proxy() : 0;
 }
 
 V8Proxy* V8Proxy::retrieve(ScriptExecutionContext* context)

diff --git a/WebCore/dom/ScriptElement.cpp b/WebCore/dom/ScriptElement.cpp
@@ -177,7 +177,7 @@ void ScriptElementData::evaluateScript(const ScriptSourceCode& sourceCode)
         return;
 
     if (Frame* frame = m_element->document()->frame()) {
-        if (!frame->script()->canExecuteScripts())
+        if (!frame->script()->canExecuteScripts(AboutToExecuteScript))
             return;
 
         m_evaluated = true;

diff --git a/WebCore/dom/XMLTokenizerLibxml2.cpp b/WebCore/dom/XMLTokenizerLibxml2.cpp
@@ -786,7 +786,7 @@ void XMLTokenizer::startElementNs(const xmlChar* xmlLocalName, const xmlChar* xm
     }
 
     ScriptController* jsProxy = m_doc->frame() ? m_doc->frame()->script() : 0;
-    if (jsProxy && m_doc->frame()->script()->canExecuteScripts())
+    if (jsProxy && m_doc->frame()->script()->canExecuteScripts(NotAboutToExecuteScript))
         jsProxy->setEventHandlerLineNumber(lineNumber());
 
     handleElementAttributes(newElement.get(), libxmlAttributes, nb_attributes, ec, m_scriptingPermission);

diff --git a/WebCore/html/HTMLMediaElement.cpp b/WebCore/html/HTMLMediaElement.cpp
@@ -1194,7 +1194,7 @@ bool HTMLMediaElement::controls() const
     Frame* frame = document()->frame();
 
     // always show controls when scripting is disabled
-    if (frame && !frame->script()->canExecuteScripts())
+    if (frame && !frame->script()->canExecuteScripts(NotAboutToExecuteScript))
         return true;
 
     return hasAttribute(controlsAttr);

diff --git a/WebCore/html/HTMLTokenizer.cpp b/WebCore/html/HTMLTokenizer.cpp
@@ -1511,7 +1511,7 @@ HTMLTokenizer::State HTMLTokenizer::parseTag(SegmentedString& src, State state)
                 m_scriptTagSrcAttrValue = String();
                 m_scriptTagCharsetAttrValue = String();
                 if (m_currentToken.attrs && !m_fragment) {
-                    if (m_doc->frame() && m_doc->frame()->script()->canExecuteScripts()) {
+                    if (m_doc->frame() && m_doc->frame()->script()->canExecuteScripts(NotAboutToExecuteScript)) {
                         if ((a = m_currentToken.attrs->getAttributeItem(srcAttr)))
                             m_scriptTagSrcAttrValue = m_doc->completeURL(deprecatedParseURL(a->value())).string();
                     }
@@ -1921,7 +1921,7 @@ void HTMLTokenizer::finish()
 PassRefPtr<Node> HTMLTokenizer::processToken()
 {
     ScriptController* scriptController = (!m_fragment && m_doc->frame()) ? m_doc->frame()->script() : 0;
-    if (scriptController && scriptController->canExecuteScripts())
+    if (scriptController && scriptController->canExecuteScripts(NotAboutToExecuteScript))
         // FIXME: Why isn't this m_currentScriptTagStartLineNumber?  I suspect this is wrong.
         scriptController->setEventHandlerLineNumber(m_currentTagStartLineNumber + 1); // Script line numbers are 1 based.
     if (m_dest > m_buffer) {

diff --git a/WebCore/inspector/InspectorController.cpp b/WebCore/inspector/InspectorController.cpp
@@ -230,7 +230,7 @@ static bool canPassNodeToJavaScript(Node* node)
     if (!node)
         return false;
     Frame* frame = node->document()->frame();
-    return frame && frame->script()->canExecuteScripts();
+    return frame && frame->script()->canExecuteScripts(NotAboutToExecuteScript);
 }
 
 void InspectorController::inspect(Node* node)